Anne,
One speed up would be to replace your sea with a single polygon:
Here is a small scale comparison:
ice = Plot3D[Sin[x]Sin[y], {x, 0, 9}, {y, 0, 9}];
sea = Graphics3D[{Polygon[{{0, 0, 0}, {9, 0, 0}, {9, 9, 0}, {0, 9, 0}}]}]
Show[ice, sea, PlotRange -> {0, 1}] // Timing // First
0.55 Second
sea2 = ListPlot3D[Table[0.01, {x, 0, 9, .5}, {y, 0, 9, .5}],
MeshRange -> {{0, 9}, {0, 9}}];
Show[ice, sea2, PlotRange -> {0, 1}] // Timing//fFirst
3.24 Second-
Allan
---------------------
Allan Hayes
Mathematica Training and Consulting
Leicester UK
www.haystack.demon.co.uk
hay at haystack.demon.co.uk
Voice: +44 (0)116 271 4198
Fax: +44 (0)870 164 0565
"anne barker" <anne.barker at nrc.ca> wrote in message
news:8nlhsb$9ei at smc.vnet.net...
> Hello.
>
> I have 20 very large data files, with which I am creating a series of
> surface graphics, which are in turn converted into an avi. animation. The
> data represent an ice surface. I can clipfill the original data file to
> create a "water surface" where there is no ice present.
>
> I need to insert 3 Graphics3D objects into the surface graphics to
represent
> various structures. For example:
> barge = Show[
> Graphics3D[{EdgeForm[], SurfaceColor[RGBColor[1, 0, 0]],
> Cuboid[{200, 117.5, -4}, {255.5, 202.5, 4}]},
> ..., DisplayFunction -> Identity]];
>
> This is fine, but the problem I encounter is that my clip-filled surface
is
> deleted once I combine the Surface Graphic and the Graphic3D item, as the
> entire graphics becomes a Graphics3D file, rather than a SurfaceGraphics
> file.
>
> I have, in the past, created a surface:
>
> surface = ListPlot3D[Table[0.01, {x, 1, 500, 1}, {y, 1, 300, 1}],
> ..., DisplayFunction -> Identity];
> surface2 = Graphics3D[surface];
> surface3 = Insert[surface2, SurfaceColor[Hue[0.63]], {1, 1}];
>
> and then inserted this into the combined plot to represent the
"clip-filled"
> water surface. For example:
> Show[sg, barge, surface3].
>
> This was fine with smaller grids, but now I'm dealing with 500x300x12
grids,
> and each time I try to insert the surface, Mathematica (v. 4.0) crashes.
I
> have a very fast computer with a good graphics card, so I'm essentially
> wondering if there is a "simpler" way of creating this water surface so
that
> it won't chew up so much system memory. Is there a way to represent the
> structures as Surface Graphics objects?
> Would I need to use ListPlot3D, as I did for the surface, to create the
> objects?
>
> Thanks from a novice user!
> Anne
>
>
>
>
>